Hunters of ducks and geese often use decoys to bring the birds within shooting range. It seems generally agreed that the more life-like the decoys are, the better. Some form of motion, such as body movement or wing-flapping, also appears to make the decoys more effective. Decoys with movable wings have been manually operated (by pull lines), motorized, or simply moved by wind action. Decoys simulating predatory birds can be used to repel birds normally preyed upon, and decoy motion is also effective in such cases.
Moving wing attachments to otherwise standard decoys have been of various designs. These range from wings taken from live birds (and secured to the decoys with rubber bands) to wings of flexible sheet material secured to the backs of the decoys along the center line. These have been used with both full-body and silhouette decoys. Occasionally, non-game birds are simulated by decoys to lend realism to the scene where the added birds are frequently seen in the company of the game birds.